With a little help from their “Friends,” NBC’s latenight hosts saw aud levels soar last week with the series finale of the hit sitcom.

On May 6, the night of the last “Friends” episode, “The Tonight Show With Jay Leno” commanded its sixth-best showing in the demo in the 17-year history of Nielsen’s People Meters, coming during the all-important May sweep.

Broadcasting from the set of “Friends” and featuring interviews with the retiring cast members, “Leno” drew a 6.0 rating in adults 18-49 and averaged a whopping 12.6 million total viewers, according to Nielsen Media Research.

News was just as good for NBC’s “Late Night With Conan O’Brien” and “Last Call With Carson Daly” — both set all-time single night records in adults 18-49 on May 6. “O’Brien” commanded a 2.7 rating and averaged 4.9 million total viewers, while “Daly” drew a 1.7 rating and averaged 3 million total viewers.

In total viewers, “Leno” and “O’Brien” both enjoyed their biggest single-night auds since the series finale of “Seinfeld” in 1998.

For the week of May 3, “Leno” enjoyed its best showing in the demo in six years (3.0 rating, 5.9 million viewers overall).

“O’Brien” racked up its fourth-most watched week ever (1.5 in 18-49, 3.1 million viewers), and “Daly” its second most-watched (1.0 in 18-49, 1.9 million viewers).

CBS’ “Late Show With David Letterman” (1.7 in 18-49, 4.4 million) continues to post strong growth over last year but trailed well behind “Leno” for the week of May 3.

The Eye’s “Late Late Show With Craig Kilborn” (0.8 in 18-49, 1.8 million) beat out the overlapping “Jimmy Kimmel Live” on ABC (0.7 in 18-49, 1.6 million).